[Compressed NFTs] Transfer with zero length proof

[raulriera]

Description

From the docs the recommendation is to prune it from the proofs but that results in an empty array and the transfer will fail.

In the TypeScript code example above, we are first taking a slice of our "full proof", starting at the beginning of the array, and ensuring we only have proof.length - canopyDepth number of proof values. This will remove the portion of the proof that is already stored on-chain in the tree's canopy.

There are situations where the canopyDepth and full proof are the same resulting in a zero length proof that will fail a transfer with Proof is empty. Example NFT would be any of the Tensorians NFTs https://www.tensor.trade/trade/tensorians

[ngundotra]

@raulriera I haven't heard of any issues with zero length proofs, but if you can provide a code sample I can take a look.

I'll add a test to the test suite & then close this issue.

cc @richwardwu